Guiding catheters are instruments that allow a physician to access and cannulate vessels in a patient's heart for conducting various medical procedures, including venography and implanting of cardiac pacing devices. Cannulating heart vessels requires navigating a small diameter, flexible guide through the tortuous vasculature into a heart chamber, and then into a destination heart vessel. Once the destination heart vessel is reached, the catheter acts as a conduit for insertion of payloads into the vessel.
A commonly accessed destination vessel for cardiac pacing lead insertion is the coronary sinus. A pre-shaped guiding catheter is typically used to blindly locate the coronary sinus ostium. This endeavor, however, is complicated by the fact that the location of the coronary sinus ostium may vary appreciably from one patient to another, especially among patients with diseased hearts. Oftentimes, the clinician is entirely unable to locate the coronary sinus ostium using the guiding catheter, and must resort to finding the ostium by “mapping” (interpreting localized bipolar waveforms) using an electrophysiological (EP) catheter and an ECG monitor. After the ostium is located, the guiding catheter is typically used to inject radiographic contrast media into the coronary sinus to highlight the associated venous system, and then a pacing lead is installed within one of the coronary branches.
Complicating this scenario is the dynamic structural deformation of the heart chambers that occurs from normal cardiac activity during the procedure. This further increases the difficulty of guiding a catheter to its destination. Presently, a considerable amount of time is often spent by the physician when manipulating such catheters within cardiac structures, such as the right atrium, simply trying to locate an anatomical feature of interest, such as the coronary sinus ostium.
Guiding catheter systems are typically configured with a profile that is optimized for the intended method of access. In the case of accessing the coronary sinus via the right atrium, a catheter with a distal contour including a relatively sharp bend will point the catheter towards the likely location of the coronary sinus once the right atrium is reached. The contours of pre-shaped guiding catheters are generally fixed, and this is typically achieved in production by constraining the distal end within a shaping fixture while warming them until they assume the intended shape (i.e., by “heat setting” their polymer shaft).
Guiding catheters are sometimes introduced over a pre-shaped guide wire that is inserted into the desired location first. The guide wire is typically small and maneuverable, and can be pre-shaped for the desired venous path. However, utilizing a guide wire prior to introducing the guide catheter is more time consuming as two operations are required. Shortening the time required to cannulate the desired vessels is desirable as it reduces the total procedure time and reduces trauma to the patient.
There is a need for an improved guide catheter having enhanced maneuvering capabilities and methods using same for accessing blood vessels of interest and for cannulating those vessels. There exists a further need for a guiding catheter and methods of using same that accounts for anatomical variation and defects with the destination structures. The present invention fulfills these and other needs, and addresses other deficiencies of prior art implementations and techniques.